\psset{unit=0.5,algebraic}
\begin{pspicture*}(-4,-3)(4,3)
\psaxes[labelFontSize=\scriptstyle,ticksize=-3pt 0,labelsep=2pt]{<->}(0,0)(-4,-3)(4,3)
\psplot[linecolor=blue]{-3.5}{-0.0001}{1/x}
\psplot[linecolor=blue]{0.0001}{3.5}{1/x}
\end{pspicture*}